Sheet-metal can



(No Model.)

J. W. HILL & R. P. MoKAY.

SHEET METAL CAN.

No. 577,552. Patented Feb. 23, 1897.

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w viimeowo UNITED STATES PATENT GFFICE.

JOSEPH W. HILL AND RICHARD P. MCKAY, OF PORTLAND, OREGON.

SHEET-METAL CAN.

SPECIFICATION forming part of Letters Patent No. 577,552, dated February23, 1897. Application filed January 25, 1896. Serial No. 576,799. (Nomodel.)

To all whom it may concern.-

Be it known that we, JOSEPH WV. HILL and RICHARD P. MOKAY, citizens ofthe United States, residing at Portland, in the county of Multnomah andState of Oregon, have invented certain new and useful Improvements inSheet-Metal Cans; and we do declare the following to be a full, clear,and exact description of the invention, such as will enable othersskilled in the art to which it appertains to make and use thesame,reference being had to the accompanying drawings, and to the letters ofreference marked thereon, which form a part of this specification.

This invention relates to key-openin g coated sheet-metal cans orvessels of the class in which a strip of tin is located within the sheetmetal forming the body of the vessel and embedded in a fold of the same,one end of this strip protruding outside of the vessel, whereby saidstrip may be seized and drawn outward by means of a key,'thus severingthe metal exterior of the vessel and giving access to its contents.

This invention is in the nature of an improvement upon theconstructi'onof any or all key-opening cans in which the sheet metal isweakened in any way along the line or lines of separation and inwhich atongue of the metal between these weakened lines projects and by theengaging of which with a key the can may be opened, or in that class ofcans in which a wire is embedded in the can or soldered onto the canalong the interior in a fold or groove of weakened metal and which areopened by drawing the said wire through this weakened metal.

In our invention the metal is not weakened in any way, as it isunnecessary to do so for the purpose, the result being better and moreeconomically accomplished by means of a strip of tin folded into thebody of the can in the manner hereinafter described. The coating ofsheet metal is in no wise destroyed by using this strip of tin, as inthe case where the metal is broken or weakened, and by not using anywire to come in contact with the contents of the can said contents arenot discolored nor injured by rusting of said wire. In our improved modeof manufacture there is no solder employed in any manner upon the insideof the can. This is an important feature, since it is well known thatsolder is harmful in many kinds of canned goods, because the combinationof acids comes in contact with the lead used in soldering, therebyforming the injurious salts of lead.

This invention does away completely with all the various methodsheretofore employed of weakening the sheet metal by breaking, cutting,or thinning by rollers, by dies, or by a single die cooperating with ananvil, or by any other suitable device or devices.

In the drawings, Figure 1 is a plan of the blank for the can-body. Fig.2 shows the blank folded with the cutting-strip inclosed in said fold.Fig. 3 is an elevation of the completed can, showing the effect of theoperation of the key in opening it. Fig. 4 is a detail showing the foldand one of the end seams in section. Fig. 5 is a similar View showingthe can opened.

The body-blank A, Fig. 1, is a rectangular sheet, having in one end,near the top, a T- shaped notch a, the width of the stem of the Tbeing-equal to the width of the strip to be torn from the fold, whileits length is the same as that of the lap which is to form the sideseam.

Bymeans of a special machine, which will form the subject of anotherapplication,.the blank A is folded lengthwise along the lines a a intothe shape shown in Fig. 2, astrip of tin or other sheet metal B being atthe same time inclosed in and filling the flat fold. The inner edges ofthe fold preferably meet along the line a as seen in Fig. 4, but in anyevent the edges of the strip 13 are protected from contact with thecontents of the can. The folded sheet and strip are then formed into acan-body, the edge a being lapped over the edge a to the line of,corresponding with the end of the notch a and soldered on the outside.The heads C are then put on, each having an annular countersink c toform a flange c, fitting inside the can-body, and an outer flange cfitting down over the outside of said body, the edge of the flange 0being doubled at c to inclose the raw edge. The flange is soldered tothe bodyon the outside. We do not limit ourselves, however, to thisconstruction of head and joint, since any suitable mode of forming theheads and uniting them to the body may be employed. lVe prefer, however,to use a seam which will project beyond the body of the can to or nearlyto the line of the flat fold, so that when the cans are packed they willbe in cont-act or nearly so at top and bottom as well as at the level ofthe fold. It will thus be seen that our flat fold is superior to anyother shape in that it economizes space and obviates any tendency of thefold on one can to ride up over the fold on an adjacent can. The end ofthe cuttingstrip B is left projecting at the side seam, lying flatagainst the side of the can. It is thus readily engaged by a key D,preferably composed of apiece of stout wire bent at one end to form ahandle d and flattened at the other end to permit the cutting of a slotd, which is slipped upon the end of the strip B. \Vhen the key is turnedto roll up the strip, the metal composing the fold is torn apart alongthe lines a, the portion between said lines being wound up on the keywith the strip B. This leaves the upper part of the can free to belifted off, as shown in Fig. 5.

In the manufacture of this invention but one extra machine is needed andthis at one operation automatically forms, folds, and places the narrowstrip of tin therein. The shape of this fold is such that there is noneed of soldering or bending of the strip of tin at the inner end tocause it to remain in the fold while it is being wound up by the key.

The steps in our method of forming the can above described may be summedup as follows: The coated blank of sheet metal is suitably notched toprovide for the projecting of the strip of tin through the body-blank,or it may be folded into the body-blank without notching, or after thestrip is folded it may be treated exactly as a plain body-blank is usedin the formation of a can under ordinary circumstances. The strip of tinfolded into the body-blank forms no obstacle to the soldering on a hornin the usual manner, as it is no objection if the solder does cover thestrip of tin, although it is unnecessary to keep it in place, and itdoes no harm because the action of the key is such that it will tearloose and tear open the can even if the strip is soldered to the body ofthe can unintentionally. The heads may be put on and the can completedin the usual manner. The action of our combination key and strip of tincontained in the fold of the body of the can of our invention ispositive, thus obviating the difliculty experienced in many devices forkey-opening cans, which have been found to be impracticable because ofincreased cost of manufacture or because of the difficulty arising whenthe weakened lines or thin portions of the can-body are not exactlyparallel and of the same thickness. The portion of the body containedbetween these lines does not tear evenly, but will tear obliquely ortransversely to the line of separation and break off, thus defeating theobject in view.

In Figs. 4 and 5 we have shown the folded edges of the can as comingclose together. As a matter of fact, it would make no difference if theydid not meet by a sixteenth of an inch, since the contents of the canwould not in any case come in contact with anything but the innersurface of the tin cutting-strip and would receive no damage thereby. Incases where the can contains liquids it would be of advantage to havethe edge a slightly separated, so that when the can is opened about asmuch as is shown in Fig. 3 it can be turned over to let part of thecontents run out.

One other point of advantage worth noting is this: In all other devicesfor opening cans by means of tearing out the body with the aid of a keyacting in conjunction with a part of the body of the can running alongor between weakened parallel lines and in that class of cans in which awire is used to cut the can a more or less rough or serrated edge isleft 011 the upper part of the can where it is torn open. This is allavoided in our mode of construction and operation, as shown in Fig. 5,the surface being smooth and rounded and reinforced, formed by turningover the can-body, the edge that is out being below the top of theseparated can at a This mode of construction would not interfere withtaking out the contents of the can incase it was solid, and the personusing the can would not be in any danger of cutting the fingers on thesharp torn edges of the same.

Ive claim as our invention-- 1. A can or other vessel constructed ofsheet metal having a fiat strip of sheet metal folded in the bodythereof, the strip being made a little longer than the length of thecan-body blank, so as to project at the end, the metal of the body ofthe can having been in no way weakened or prepared for the reception ofthis strip, except the folding, substantially as described.

2. The can-body having a strip of sheet metal contained within anoutwardlyprojecting ilat fold, which extends around the can-body, saidstrip lying parallel with said body, one end of said strip terminatingwith the outside edge of the lapped side seam and the other end of saidstrip projecting a convenient distance from the other edge of the lappedseam whereby said strip may be engaged bya proper key, so that when thekey is turned, the contained strip and the outer portion of the fold arewound up together and the body severed along the upper and lower edgesof the fold, substantially as described.

3. A sheet-metal can having a portion of its body folded into anontwardly-projecting fold or bead, composed of the flat portions a alying against the body of the can, and the flat portion a a lyingparallel with the body of rectangular metal sheet A having in one endthe can, the folds a being at the upper and near the top, the T-shapednotch a, substanlower edges of said flat fold, and a flat cuttially asdescribed. ting-strip of metal inclosed in and filling said In testimonywhereof we affix our signa- 5 5 fold and lying parallel with saidcan-body, tures in presence of two witnesses.

whereby the fold and inclosed strip project but slightly beyond the wallof the can and AY offer a broad, fiat outer surface to come in contactWith adjacent cans when packed, sub- Witnesses: 1 o stantially asdescribed. L. L. WARTHEN,

4. A blank for a can-body, consisting of the E. O. BRONAUGH, Jr.

